The Japanese A Bomb

I saw a program on cable a couple of years ago that described Japanese A bomb development. It mentioned a captured Japanese general who described the program and a detonation of the weapon in what is now North Korea just days before the their surrender.

Does anyone recall this program?

 

Greetings,

did you read this ?

Go Wikipedia !

Regards,
TBA

 

Regarding the supposed "U-235" from Germany, there is no indication that the Nazis ever developed practical separation technology - so I doubt that it was really U-235. The US built acres of factories with tens of thousands of workers, and only managed to produce enough fissionable material for three weapons by the end of the war. Neither Japan nor Germany had any facilities even close to this scale - if they did, those buildings would have made fine bombing targets.

As a footnote, some experimental German uranium was found this year:

 

Good info. Thanks!

 

Steve, I do remember that program. It would be interesting to do a site survey of that North Korean island to discover any unusual radioactivity in the area. If the Dear Leader would allow it, that is.

 

That is a great Liberator Avatar? Where did you get that? Were you on a B-24? 15th AAF? My Dad was a B-24 pilot. They were shot up into a forced landing on Vis once and had to bail out two other times. What is your story? God Bless!

 

The island where Japan's nuclear test occured was on one of the islands in Yonghung-Man Gulf however which island precisely is not clear. There was said to be a village on the island and with Google Earth you can find one or two such islands with military settlements on them today.

During 1944 Nichitsu developed ten fergussonite mines across Korea and recovered 500,000 tonnes of Uranium ores with essentially slave labour.

 

They may well have recovered all those tons of Uranium ore, but the Japanese had absolutely NO WAY of refining the isotope 235 out of that low grade ore. Even in the best of ores, U-238 itself appears at less than 60%, and then only .07% of that holds the fissionible isotope of U-235.

The only separation units the Japanese had were those which had been donated to them by Lawrence, and the one they had built by copying his design. That magnetic separation process would not have allowed the Japanese to separate any useable amount in all the years they had their cyclotrons operating to make an explosive device. Not doable, not feasible, not really even a "what if".

 

Not correct. IJN’s centrifuges were developed by a company specialised in precision ship gyros, Hokushine Electric Company with assistance from Tokyo Keiki Electric Co. These were built under contract by heavy engineering firm Sumitomo.

The Navy F-Go project under Arakatsu developed centrifuges with rotors made from alloys of rare earth metals and these could spin at prodidious speeds of 100,000 to 150,000 rpm. As a point of reference the fastest German centrifuges the Hellage Mark IIIB installed in an underground enrichment plant at Kandern could only reach 60,000 rpm.

Your domestic washing machine likely only spins at 240rpm. The efficiency of a centrifuge at enrichment is inversely proportional to it's speed and the faster it spins the more efficient.

Whilst Manhattan laboured away with gaseous diffusion, the centrifuges used by Germany were thirty times more efficient as measured by separative work units. The Japanese machines developed by Sakae Shimizu were at least double the efficiency of German machines.

IIRC the Hellage mark IIIB per machine, could enrich 2kg of Uranium per day producing 200 grams enriched by 7%.

Given the lack of access to archive material about Japan's enrichment schemes it is in the realm of conjecture whether they could, or could not and even how they achieved it.

 

I think a more interesting 'what if' would be to consider what the Japanese might have done if they did have a working prototype bomb when the American attacks had taken place - It certainly seems possible that Japan could have found a way to deliver one to somewhere on the West coast or perhaps one of the Pacific Islands.

Do you think they would have used it?

And if they did, considering the time it took the Americans to get enough material together to make further bombs what effect might it have had on the Pacific war plans?

Maybe this belongs in the 'What if' section, so sorry if it shouldn't be here!

 

You left out the word "alleged".

 

One might as easily describe it as unacknowleged accounts of A-bomb blasts.

David Snell's account is familiar to most, but few have heard the Report, Interrogation of Otogoro Natsume by Dr H Kelly, October 31 1946, NA, RG 224, Box 3.

By so late in the war Japan lacked any viable means to deliver a nuclear weapon to it's enemies. That was the real issue.

 

As easily yes. As correctly no.

I'd hardly say that. It is the most famous account of a Japanese atomic test but as: http://en.wikipedia.org/wiki/David_Snell_(journalist)
says:

Care to tell us what's in it?

 

How come in the past 65 years, only one or two Japanese nationals knew about this "supposed" atomic weapon when thousands would have had to know about it, yet have never talked?

How convenient.

 

Don't tell me what is in it, post the entire report in its original format. Especially since you seem to know where to go to put your hands on it.

Otherwise, I know a guy, who has a cousin, who knows a guy, who once met someone, who once met a Dr Kelly, who told him that he knew nothing about Japanese atomic bombs, so that would seem to prove such never existed.

 

I think I met that guy once!

 

For what its worth, here is the article:

1946 Atlanta Constitution Atom Bomb Articles

 

I remain skeptical, the Japanese lacked not only the raw material (U-238), they lacked the massive electrical production ability to match either Hanford (plutonium) or Oak Ridge (U-235). The Soviets did match the Western Allies, and darned soon, but I doubt it was because of captured Japanese from Korea since it took until 1949. They had more than competent physicists, what they lacked were the engineering designs. It was those which the MED spies gave to the Stalin dominated USSR. It still took them four years to make an "implossion" plutonium bomb. The implossion construction was the "hitch".

I think that Stalin was shocked at how "fast" we (America) produced our first two bombs of different designs, not that the bombs could be built. His spies had kept him pretty well informed about the progress, and his own scientists were no slouches in the field.

I still find the Japanese claims to be less than credible. Sorry.

 

There is indeed substantial questions on the validity of Snell's articles. See:
Japanese nuclear weapon program - Wikipedia, the free encyclopedia

 

Quoting Wikipedia is the best you've got?